A study of Central Valley housing demand forecasts a shift from the mass construction of single-family homes to building many more apartments and condominiums.

Commissioned by the Council of Infill Builders, the report found the region's existing stock of detached homes on lots of more than 6,000 square feet may be sufficient to meet demand through 2050. As a result, nearly half of all new housing built in coming years will be attached dwellings, said the report's author, Arthur C. Nelson, director of the Metropolitan Research Center at the University of Utah.

"For the Valley as a whole, what we're looking at is moving from about 30 percent attached housing forms in 2010 to 35 percent in 2050," Nelson said. "To get there, it means about 45 percent of all new housing built will be some kind of attached, whether owned or rented."

The shift is being driven by changing demographics. There's a growing population of aging seniors who will be looking for smaller, more manageable housing, as well as a younger populace who also will seek smaller housing or can't afford larger, detached homes.

It won't be a sudden, dramatic change. Single-family homes will continue to constitute the majority of new housing, but the percentage of attached projects will grow.

"We're kind of looking at a slow, glacial change over time for the Valley," Nelson said.

In addition, the demand for smaller-lot, single-family homes within walking distance of jobs and shopping is strong and growing, the report said.

"We need to end sprawling development patterns in order to ease the financial burden on local governments and capture the next wave of housing demand," said David Mogavero, a Council of Infill Builders board member and Sacramento real estate developer and architect.

The construction of single-family homes on large lots in subdivisions far from city centers was fostered by a combination of federal housing and transportation policies; the availability of cheap gasoline and the automobile; and state and local programs, such as building new schools instead of investing in existing schools in old neighborhoods.

As a result, Mogavero said, "Stockton has suffered literally from 50 to 60 years of sprawl."

But there are certainly opportunities to turn that around, he added.

Mogavero, who has worked on projects in Stockton and recently toured the city looking for infill development opportunities, said local policies aimed at fostering such projects could include using transportation funding to create more bicycle lanes and "bulb-out" curb extensions at intersections to increase pedestrian safety and encourage walking.

He was particularly struck by Stockton's Magnolia District, which Mogavero described as "a classic early 20th century, late 19th century community, built around people walking."

"Some reinvestment in the Magnolia District would be great to improve traffic safety in that neighborhood," he said

A focus on infill development could be accomplished with only minor changes to zoning and development regulations, the proponents argue. That would foster the redevelopment of low-density urban and suburban centers and transform existing commercial buildings and vacant land.

"The result will be more efficient use of land and less farmland lost to development," an Infill Builders statement said.